The parts of the flowers are represented using various shapes in a floral diagram. A floral diagram provides information about the number of parts of a flower, their arrangement and the relation they have with one another. Different parts of a flower like calyx, corolla, androecium and gynoecium are drawn in successive whorls. The outer part of the flower, which consists of the corolla and calyx is called the perianth. Perianth refers to the condition when there is no distinction between sepals and petals. The individual parts of the perianth are known as tepals. Hence, the individual floral unit marked in the diagram is tepal.